Passivator for treating aluminum foil and preparation method thereof

The invention discloses a passivator for treating an aluminum foil, and relates to the technical field of metal material surface treatment. The passivator comprises 0.3-1 part of a chromium solution,0.5-2 parts of modified phenolic resin, 2-5 parts of potassium zirconium carbonate, 2-5 parts of sodium diisobutyl naphthalene sulfonate, 0.5-2 parts of barium tellurate, 40-55 parts of ethanol and 35-40 parts of water. The chromium solution, the modified phenolic resin, the ethanol and the water are mixed and uniformly stirred, and then standing is carried out to obtain a mixed solution; and thepotassium zirconium carbonate, the sodium diisobutyl naphthalene sulfonate and the barium tellurate are sequentially added into the mixed solution, and heating and standing are carried out to obtain the passivator. The passivator is prepared by taking the chromium solution and the phenolic resin as basic raw materials, an oxide film layer can be formed on the surface of the aluminum foil, and thecorrosion resistance and th